In photovoltaic (PV) module mounting clamp designs for framed modules, the module mounting clamp is best slid over the end of the torque tube prior to installation of the tube. These standard-module mounting clamps are relatively small, usually 300-600 mm in width. The short clamps are easy to slide onto the end of the torque tube and transport well while mounted onto the torque tube across the field and therefore result in an efficient installation process.
Frameless PV modules, especially glass modules which incorporate glass as both the front and back sheets of the module are becoming more popular due to benefits such as better fire protection, improved moisture barriers, and because they exhibit less overall lifetime degradation. To mount unframed PV modules, a longer structure is required to support the unframed glass of the module. One such unframed module supporting structure consists of module mounting rails. These rails are typically fabricated from roll formed steel and may be multiple meters in length. The module mounting rails need to be attached to the torque tubes of the solar tracker. Additionally, it may be desirable to mount multiple framed modules in landscape to achieve a different aspect ratio for the array or to achieve better support for the modules in high load scenarios onto module mounting rails.
However, it is not practical to have a mount in which the installer needs to thread long mounting rails over the end of the torque tube and then transport them across the field to install as can be done with the short (0.3 meter) module mounting clamps for framed modules. The long length (2-3 meters) of the module mounting rails would hang from the torque tube and would likely get damaged during assembly and tracker installation.
In addition, while torque tubes can be any shape, octagonal is a common and advantageous shape. The octagon is a unique shape and resembles a round tube with eight flat sides. However, it is not readily suitable to attachment by a straight bolt or simple standard hardware.
Accordingly, there is a need for a mounting bracket assembly that can be placed over a torque tube at any position along the length of the tube. There is also a need for a torque tube mounting bracket that fits over an octagonal tube. In addition, a need exists for a mounting bracket assembly that facilitates attachment of mounting rails for frameless solar modules to a torque tube.